Heat the olive oil in a large skillet over medium-high heat. Add the beef cubes and brown them on all sides for about 5 minutes. Transfer the beef to the slow cooker.
Add the carrots, parsnips, potatoes, onion, and garlic to the slow cooker.
In a bowl, whisk together the beef broth, tomato paste, Worcestershire sauce, thyme, rosemary, salt, and pepper. Pour this mixture over the meat and vegetables.
Tuck the bay leaves into the liquid. Cover and cook on low for 8 hours or on high for 4 to 5 hours until the beef is very tender.
Remove the bay leaves before serving. Stir gently to combine everything.